The present invention relates to a device for checking metal pieces, intended more particularly for coins or tokens, for example for automatic paying of toll charges on motorways or for parking, but which could also be used for other purposes for example for sorting out bearings or gear-wheels.
Different constructions are known for devices for checking coins in automatic toll charge paying stations. However with most of these checking devices, authentication of a large number of different coins cannot be provided with sufficient reliability and rapidity, since some of these coins may be very closely related in their physical appearance, particularly if different foreign coins must also be taken into account.